... design or drawings. We have been in this industry for more than 10 years.Our factory owns electrical discharge machining ... : Copper, Brass, Aluminum, Stainless Steel, Steel alloy, etc.2. Specification: OEM, according to customers' drawing or sample.3. Precision: +/-0 ... ) QC inspects after mass production finished 4) International sales who were trained the technical know-how spot check before shipping.